1. Field of the Invention
The present invention relates to a minute electrode, a photoelectric conversion device including the minute electrode, and manufacturing methods thereof.
2. Description of the Related Art
In recent years, a photoelectric conversion device that generates power without carbon dioxide emissions has attracted attention as a countermeasure against global warming. A solar battery using a crystalline silicon substrate such as a single crystal silicon substrate or a polycrystalline silicon substrate is known as a typical example of the photoelectric conversion device.
In general, a grid electrode which is used for current collection and serves as a wiring is provided on a light-receiving surface side of a solar battery. The grid electrode is formed of a metal film or a conductive resin film, and a region which is the shade of the grid electrode is a region which does not directly contribute to power generation. Thus, the width of the grid electrode is expected to be small, so that the area of the grid electrode is reduced.
It is preferable that a cross section alone the short-axis of the grid electrode have a shape with a high aspect ratio so as not to increase resistance and the area of the cross section be increased when the width of the grid electrode is made small. As a means for forming such a grid electrode, formation of a built-in electrode is being attempted (see Patent Document 1 and Non Patent Document 1).
The technique disclosed in Patent Document 1 is a method in which a dicing process is performed on a crystalline silicon substrate to form a groove portion and the groove portion is filled with a conductive resin under a reduced pressure by a screen printing method. Further; the technique disclosed in Non Patent Document 1 is a method in which a laser process is performed on a crystalline silicon substrate to form a groove portion and the groove portion is filled with a conductive film by an electroless plating method.